dpd is a technique to linearize the nonlinear pa in a rf chain to achieve the best energy efficiency while maintaining the spectral mask requirement [1]}. It is customary to implement dpd using parametric models. For simplicity, dpd parameters are mostly optimized at the transmitter side, which requires a feedback data acquisition path to collect the PA output signal [2]}. To capture the full-band behavior of the PA for DPD optimization, high sampling rate feedback adc in the feedback path are needed, which is challenging for wideband signals. High sampling rate adc add a huge cost, which increases linearly with the number of rf chains in massive mimo [3]}, where each RF chain may require a separate feedback path [2]}.
